Traditional single-mode cables for the outside plant or outdoor/indoor applications have a somewhat complicated structure. In order to ensure low signal attenuation, cable designs must isolate fibers from forces that cause macrobending attenuation. A typical outside plant cable design will enclose the fibers in one or more tubes with water-blocking material, protect those tubes with an outer jacket, and typically use some sort of rigid strength member to limit thermal expansion and contraction of the cable at temperature extremes.
A typical indoor-outdoor style premises drop cable utilizes a tight buffer directly outside the fibers to limit contact between the fiber and the rest of the cable. Like the tube in the outside plant example above, the tight buffer isolates the actual fiber from forces causing macrobending attenuation. However, these approaches require a complicated, costly multi-step process to package the fiber.